Hi All,
I have a real life problem that I need to solve (not homework). If anyone could take a look and see if I am approaching this problem correctly I will greatly appreciate your help.
I need to predict the percentage of bad die I will not detect using the following scenario.
I know that my average failure die failure rate is 7%
I know my failure rate varies from wafer to wafer
6 Die are tested per wafer, if 2 or more die fail, the entire wafer is rejected.
I've used the binomial probablity formula to predict the probabiliy that a wafer will pass dependent upon the % of bad die per wafer. Can I assume that my average failure rate will be equal to the average failure rate of the population? Or, do I also need to know the distribution of die failure rates on the individual wafers (See column A of attached spreadsheet)?
Please let me know if I am approaching the problem correctly or if I should be using a different method.
Thanks,
SerrenaC
Last edited by SerrenaC; 12-15-2006 at 02:35 AM.
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